Engineering researchers use laser to "weld" neurons

A research team based in the Faculty of Engineering has developed a method of connecting neurons, using ultrashort laser pulses—a breakthrough technique that opens the door to new medical research and treatment opportunities.

The team is the first ever to find a way to bond neurons and in doing so, has given researchers a powerful new tool. Neurons are cells in the nervous system that are responsible for transferring information between the brain and the rest of the body.

“The immediate application is for researchers. They finally have a new tool to do what they have not been able to do before,” said Nir Katchinskiy, a second-year PhD student in Electrical Engineering who led the study. “We’re engineers. We come up with tools that provide potential.”

Katchinskiy had a real-life application in mind when he started the project. “I was really interested in the nervous system—if you have a severed nerve, you can’t repair it,” he said. “My thought was, what if we could ‘weld’ it back up right after it’s injured?”

To conduct the study, two neurons, put in a special solution that prevents them from sticking together, were brought into contact with each other. Femtosecond laser pulses—each ultrashort pulse occurring every 10-15 seconds—were delivered to the meeting point of the two cells. Although the outside layer of the cells was partially compromised, the inside of that protective layer remained intact. As a result, the two cells established solid bonds forming a common membrane at the targeted area.

Throughout multiple experiments, the cells remained viable and the connection strong. It took the neurons 15 milliseconds to stick to each other—the process would have taken hours to occur naturally.